PtNi Alloy Research Articles

Nitrogen-doped carbon nanosheet confined PtNi alloy for efficient acidic electrocatalytic hydrogen evolution reaction

Low intrinsic electrocatalytic activity and inferior conductivity limit the application of Ni/NC in acidic electrocatalytic hydrogen evolution reaction (HER). Herein, we prepared nitrogen-doped carbon nanosheet confined PtNi alloy electrocatalysts (PtNi/NC-10) using PtCl62− electrostatic adsorption coupling melamine pyrolysis nitriding strategy. PtNi alloying was confirmed by the crystallinity decrease and lattice expansion of Ni/NC. The alloying and confinement effect of Metal-Organic Frameworks (MOFs) suppresses the oxidation and agglomeration of metal nanoparticles during pyrolysis, thus significantly reducing particle size, increasing specific surface area, and promoting the exposure of active sites. The strong electronic interaction between Pt and Ni optimizeds the surface charge distribution, enhancing the adsorption of H species on electron-rich Pt sites, thereby improving reaction kinetics. In addition, PtNi alloying improves the conductivity of the material, accelerating charge transfer and proton transport. Consequently, the prepared PtNi/NC-10 exhibits superior HER performance than Ni/NC in 0.5 M H2SO4 solution, even comparable to commercial 20 wt% Pt/C, with the overpotentials of 35 mV at 0.01 A cm−2. Furthermore, the electrocatalysts assembled PtNi/NC-10-CP‖RuO2-TFF proton exchange membrane (PEM) electrolyzer only requires 2.32 V cell voltage to achieve 1 A cm−2, presenting practical application prospects. Our work provides a novel idea for designing efficient and stable MOFs confined to alloy-based HER electrocatalysts.

In situ and one-step electrodeposition growth of PtNi alloys on Ni foam for electrochemical ammonia-nitrogen sensing

The presence of ammonia-nitrogen in aquatic ecosystems has recently been recognized as a significant threat to public and ecological health. Hence, it is crucial to develop a reliable method for accurately quantifying low levels of this pollutant in the aquatic environment. In this work, PtNi alloys of varying compositions were fabricated via a one-step in-situ electrodeposition process on a Ni foam surface. The electrochemical catalytic performances for the ammonia oxidation reaction have been measured via the cyclic voltammetry (CV) technique. The experimental results demonstrated that the PtNi alloy exhibited the highest catalytic capability with the current density of 21.387 mA cm−2 for the ammonia oxidation reaction, when the ratio of H2PtCl6·6 H2O and Ni(NO3)2·6 H2O was 3:1 with the deposition time of 1500 s. Under the most favorable conditions, the electrochemical detection performance of the PtNi alloy in detecting ammonia-nitrogen has been extensively assessed based on the differential pulse voltammetry (DPV) technique. The experiments confirmed that the PtNi alloy demonstrated an outstanding sensitivity, reaching a remarkable value of 0.0255 mA µM−1, with a broad linear range from 3 µM to 500 µM. The PtNi alloy also demonstrated a remarkable low limit detection of 0.89 µM. In addition, Further evaluation of the anti-interference ability, reproducibility, stability and recovery in real sample analysis including tap water, lake water and sea water revealed that the PtNi alloy exhibited superior performance for detecting ammonia-nitrogen.

Integrating Pt single atoms and Mo into PtNi/C through Mo doping-displacement synchronisation strategy for enhanced HER at all pH values

This paper proposes a Mo doping-displacement synchronization strategy to integrate Pt SAs and Mo atoms into PtNi/C, synthesizing Pt SAs/Mo-doped PtNi octahedra/carbon support catalyst (Pt SAs/Mo-PtNi/C). In this approach, Mo atoms are doped into PtNi alloy octahedra and displace some Pt atoms, forming Mo-PtNi octahedra. Importantly, the substituted Pt atoms can adhere to carbon substrate, creating Pt SAs. Pt SAs/Mo-PtNi/C exhibits lower overpotentials (38, 59, and 110 mV at 10 mA cm−2) and smaller Tafel slopes (44, 51, and 139 mV dec-1) in acidic, alkaline, and neutral environments. Additionally, the electron pathway of Mo-PtNi → Pt SAs/C has been confirmed, and Pt SAs/Mo-PtNi/C exhibits an optimized hydrogen adsorption energy (ΔGH*=-0.29 eV). Furthermore, catalyzed by Pt SAs/Mo-PtNi/C, the H-O bond length of H2O extends to 1.11 Å and the bond angle reduces to 102.741°, directly confirming that the Pt SAs and doped Mo could facilitate H-O bond breaking. The proposed Mo doping-displacement synchronization strategy not only simplifies the fabrication process of Pt SAs catalyst, but also improves its durability and activity across a wide pH range, thereby potentially advancing hydrogen production technologies.

Mechanisms of nodule formation on Ni-Pt targets during sputtering

Ni-Pt alloys are employed in the formation of Ni-Pt silicide to facilitate contact and interconnection functions in semiconductor devices. However, the formation of nodules on the Ni-Pt target during sputtering results in a reduced deposition rate and abnormal discharge, significantly impacting the film quality. This study investigates the nodule formation mechanism on the surface of Ni-Pt targets during sputtering, utilizing field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), and electron backscatter diffraction (EBSD). The findings reveal that defects and inclusion areas in the target exhibit a slower sputtering rate compared to normal areas, ultimately leading to nodule formation. Notably, platinum-rich layers were observed on the surfaces of nodules, particularly those exceeding a height of 100 μm. The variations in target surface concentration, angular distribution, and sputter yield of Ni and Pt atoms, coupled with the blocking effect of the lateral areas of nodules, contribute to the formation and compositional variation of the Pt-rich layers on the nodule surfaces.

Post mortem Study of Catalyst Degradations Occurring in High-Temperature Proton Exchange Membrane Fuel Cells Upon Start-Stop Operation

High-temperature proton exchange membrane fuel cells (HT-PEMFCs) could replace fossil fuel-based technologies for applications which cannot involve bulky/heavy cooling systems, such as aeronautics. However, severe materials degradations upon operation prevent performance retention for acceptable lifetimes. While others have already reported degradations in HT-PEMFC, post mortem characterizations of used HT-PEMFC membrane electrode assemblies (MEAs) remain scarce. Herein, HT-PEMFC performance degradation is studied by applying a startup/shutdown protocol to a short-stack operated at 160 °C; one MEA is characterized using complementary physicochemical/electrochemical techniques to identify/understand the degradation mechanisms and their origin. This start/stop operation mode (co-flow gas reactants) leads to substantial degradation inhomogeneity. For the anode, migration, coalescence, and detachment of Pt nanoparticles are witnessed induced by high-surface-area carbon support functionalization and corrosion. The anode electrochemical surface area (ECSA) remains constant at the inlet and increases significantly at the outlet, following inhomogeneous degradation of the cathode catalyst: the Ptz+ ions formed at high potential/oxidizing conditions concentrate towards the outlet, where they redeposit locally or at the anode, after diffusion/migration across the PBI membrane. Hence, the cathode ECSA decreases significantly at the inlet. Furthermore, intense Ni-leaching from the initial PtNi alloy catalyst is reported as a result of O2 mass-transport and phosphoric acid dilution inhomogeneity.

Dual performing PtNi alloys nanosheets for electrocatalytic ammonia oxidation reaction and electrochemical detection of ammonia-nitrogen

Dual performing PtNi alloys nanosheets for electrocatalytic ammonia oxidation reaction and electrochemical detection of ammonia-nitrogen

Unveiling the Composition-Dependent Catalytic Mechanism of Pt-Ni Alloys for Oxygen Reduction: A First-Principles Study.

Unveiling the composition-dependent catalytic mechanism of Pt-based alloy cathodes for the oxygen reduction reaction (ORR) helps improve the proton exchange membrane fuel cells. Using density functional theory calculations, this study investigates the ORR catalytic performance of the Pt-Ni system with various compositions (1.00, ∼0.99, 0.75, 0.50, 0.25, ∼0.01, and 0.00). The ordered solid solution PtNi3(111) system shows activity comparable to Pt(111) and is cost-effective. The Ni1/Pt(111) system, featuring a single Ni atom on the Pt(111) surface as a surface single-atom alloy (SSAA), demonstrates the highest activity with an overpotential of only 0.28, which could be further reduced to 0.21 V by decreasing the surface Ni concentration to 1/16 monolayer coverage. The predicted high activity of Ni1/Pt(111) is confirmed when considering factors such as the implicit solution environment, constant potential conditions, and protonation capability. Moreover, surface-adsorbed oxygen species driven by reaction conditions stabilize these single Ni atoms of Ni1/Pt(111) by preventing segregation and dissolution processes, thereby exhibiting a dual functionality. This study reveals the composition dependence of Pt-based alloys and highlights the stability mechanisms of SSAA catalysts during the ORR.

Formation Characteristics of Pt-Ni Alloy Nanoparticles Fabricated by Nanolamination of Atomic Layer Deposition in Hydrogen.

Forced-flow atomic layer deposition nanolamination is employed to fabricate Pt-Ni nanoparticles on XC-72, with the compositions ranging from Pt94Ni6 to Pt67Ni33. Hydrogen is used as a co-reactant for depositing Pt and Ni. The growth rate of Pt is slower than that using oxygen reactant, and the growth exhibits preferred orientation along the (111) plane. Ni shows much slower growth rate than Pt, and it is only selectively deposited on Pt, not on the substrate. Higher ratios of Ni would hinder subsequent stacking of Pt atoms, resulting in lower overall growth rate and smaller particles (1.3-2.1nm). Alloying of Pt with Ni causes shifted lattice that leads to larger lattice parameter and d-spacing as Ni fraction increases. From the electronic state analysis, Pt 4f peaks are shifted to lower binding energies with increasing the Ni content, suggesting charge transfer from Ni to Pt. Schematic of the growth behavior is proposed. Most of the alloy nanoparticles exhibit higher electrochemical surface area and oxygen reduction reaction activity than those of commercial Pt. Especially, Pt83Ni17 and Pt87Ni13 show excellent mass activities of 0.76 and 0.59AmgPt -1, respectively, higher than the DOE target of 2025, 0.44AmgPt -1.

The application of NiCrPt alloy targets for magnetron sputter deposition: Characterization of targets and deposited thin films

NiSi thin films are extensively used in advanced semiconductor devices due to their desirable electrical properties. Recently, the incorporation of platinum (Pt) into NiSi thin films, resulting in NiPtSi, has been pursued to mitigate the agglomeration of NiSi and delay its transformation into NiSi2. Typically, in semiconductor manufacturing, NiPt films are deposited onto silicon wafers through magnetron sputtering using NiPt sputtering targets. To further enhance the properties of these thin films, chromium (Cr) was introduced into the NiPt target. Initially, NiCrPt targets were fabricated through thermal mechanical treatment. Subsequently, NiCrPt thin films were deposited via magnetron sputtering using these NiCrPt targets. The study results indicate that, in comparison to NiPt targets, the addition of chromium offers several advantages: (1) it refines the grain size of NiPt in both bulk and thin film states; (2) it effectively reduces microcracks in the thin films; and (3) it increases the sputtering rate of NiCrPt targets, owing to an increased pass-through flux of 100 % and the refined grain size of the NiCrPt target. These findings provide valuable insights into the design and development of NiPt alloy sputtering targets and the production of crack-free thin films via magnetron sputtering, marking a significant advancement in the field of semiconductor manufacturing.

Low-Electronegativity Mn-Contraction of PtMn Nano-Dendrite Boosts Oxygen Reduction Durability

Although proton exchange membrane fuel cells (PEMFCs) are emerging as an efficient and green technology, their heavy reliance on scarce and exorbitant price platinum catalysts for the oxygen reduction reaction (ORR) hampers large-scale commercialization1. The strain effect, induced through the alloying of Pt with transition metals, can enhance the catalytic activity as well as reduce the platinum loading2. While this has been well documented, these catalysts’ durability has received limited attention3. In this work, we report a new class of PtMn alloy catalysts with low-electronegativity Mn-contraction which boosts the oxygen reduction durability of fuel cells. X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) reveal that the PtMn catalyst with moderate strain shows the best activity (0.53 A mg-1 at 0.9 V RHE). The PtMn alloy catalyst achieves an outstanding mass activity retention of 96% after 10,000 degradation cycles in liquid electrolyte due to the low-electronegativity of Mn, with far superior performance than highly electronegative PtNi alloys. Finally, the PtMn catalyst in PEMFC achieves an outstanding peak power density of 1.4 W cm-2 using half the loading of commercial Pt/C, and good stability over 50 h at 0.6 V in H2-O2. Figure 1

Fluorine atoms incorporation strengthens the strong metal-support interaction of PtNi@NFGC for enhanced methanol oxidation reaction performance under alkaline media

The regulatory mechanism of strong metal-support interaction (SMSI) is of great significance in improving the electrocatalytic performance for supported electrocatalysts. Here, PtNi alloy nanoparticles were deposited on N, F-codoped graphene-like carbon nanosheets (PtNi@NFGC) to construct a highly active interface for efficient methanol oxidation reaction (MOR), which solves the problems of high cost, poor activity and easy aggregation of Pt-based catalysts. Due to the high electrophilicity, F atoms doping into the carbon lattice can not only manipulate the electron structure and the state of the carbon skeleton, but also further trigger the stronger charge transfer between metal atoms and carbon support. Compared with single-doped PtNi@NGC, N, F-codoped PtNi@NFGC possesses a lower onset potential and methanol oxidation potential, higher methanol oxidation current and stronger CO tolerance. The results of the partial density of state (PDOS) simulation display that N, F-codoping promotes the electron transfer from Pt atoms to NFGC support, and leads to the d-band center shift upward, thus strengthening the oxidation degree of Pt active sites and increasing the composition of high-valent Ptx+. In-situ Raman analysis and density functional theory (DFT) results expound that F atoms embedding observably enhances the adsorption energy of Pt active centers to *OH intermediates, which not only significantly improves MOR catalytic activity, but also achieves efficient methanol dehydrogenation and alleviates CO poisoning. This customization of metal-support interface interaction by heteroatom doping strategy opens up opportunities for designing efficient supported catalysts.

Rapid Synthesis of Nickel Hydroxide/Pt-Based Alloy Heterointerface for Hydrogen Evolution in Full pH Range.

The huge application potential of nanoelectrocatalysts can become available only under the condition of scalable and reproducible preparation of nanomaterials (NMs). It is easily overlooked that most of the preparation methods for efficient platinum (Pt)-based electrocatalysts are complicated in process and time-/energy-consuming, which is not conducive to scalable and sustainable production. Herein, we propose a rapid and facile method to in situ construct a heterointerface between nickel hydroxide (Ni(OH)2) and NiPt alloy, in which the preparation steps are easy-to-operate and can be finished in 1 h. Furthermore, the ensemble effect between the Ni(OH)2 substrate and NiPt active sites benefits the water dissociation process in nonacidic conditions, while the electronic effect in NiPt contributes to the downshifted d-band center of Pt and the proper Gibbs free energy of hydrogen species. As a result, the well-designed and quickly constructed Ni(OH)2-Ni3Pt heterointerfaces reveal lower overpotentials for HER compared with most reported Pt-based and commercial Pt/C catalysts in nonacidic conditions. This study is expected to provide useful reference information for the development of facile and robust methods for the preparation of more efficient Pt-based electrocatalysts.

Hydrogen Adsorption on Ordered and Disordered Pt-Fe and Pt-Co Alloys.

The bulk properties and surface chemical reactivity of compositionally disordered Pt-Fe and Pt-Co alloys in the fcc A1 phase have been investigated theoretically in comparison to the ordered alloys of the same compositions. The results are analyzed together with our previously reported findings for Pt-Ni. Nonlinear variation is observed in lattice constant, d band center, magnetic moment, and hydrogen adsorption energy across the composition range (0-100 atomic % of Pt, x Pt). The Pt 5d states are strongly perturbed by the 3d states of the base metals, leading to notable density of states above the Fermi level and residual magnetic moments at high x Pt. Surface reactivity in terms of average H adsorption energy varies continuously with composition between the monometallic Fe-Pt and Co-Pt limits, going through a maximum around x Pt = 0.5-0.75. Close inspection reveals a significant variation in site reactivity at x Pt < 0.75, particularly with disordered Pt-Fe alloys due in part to the inherent disparity in chemical reactivity between Fe and Pt. Furthermore, the strong interaction between Fe and Pt causes Pt-rich sites to be less reactive toward H than Pt-rich sites on disordered Pt-Ni alloy surfaces, despite less compressive strain caused. These results provide theoretical underpinnings for conceptualizing and understanding the performance of these Pt-base metal alloys in key catalytic applications and for efforts to tailor Pt-alloys as catalysts.

Tailoring Zirconia Supported Intermetallic Platinum Alloy via Reactive Metal‐Support Interactions for High‐Performing Fuel Cells

AbstractDeveloping efficient and anti‐corrosive oxygen reduction reaction (ORR) catalysts is of great importance for the applications of proton exchange membrane fuel cells (PEMFCs). Herein, we report a novel approach to prepare metal oxides supported intermetallic Pt alloy nanoparticles (NPs) via the reactive metal‐support interaction (RMSI) as ORR catalysts, using Ni‐doped cubic ZrO2 (Ni/ZrO2) supported L10−PtNi NPs as a proof of concept. Benefiting from the Ni migration during RMSI, the oxygen vacancy concentrations in the support are increased, leading to an electron enrichment of Pt. The optimal L10−PtNi−Ni/ZrO2−RMSI catalyst achieves remarkably low mass activity (MA) loss (17.8 %) after 400,000 accelerated durability test cycles in a half‐cell and exceptional PEMFC performance (MA=0.76 A mgPt−1 at 0.9 V, peak power density=1.52/0.92 W cm−2 in H2−O2/−air, and 18.4 % MA decay after 30,000 cycles), representing the best reported Pt‐based ORR catalysts without carbon supports. Density functional theory (DFT) calculations reveal that L10−PtNi−Ni/ZrO2−RMSI requires a lower energetic barrier for ORR than L10−PtNi−Ni/ZrO2 (direct loading), which is ascribed to a decreased Bader charge transfer between Pt and *OH, and the improved stability of L10−PtNi−Ni/ZrO2−RMSI compared to L10−PtNi−C can be contributed to the increased adhesion energy and Ni vacancy formation energy within the PtNi alloy.

Tailoring Zirconia Supported Intermetallic Platinum Alloy via Reactive Metal-Support Interactions for High-Performing Fuel Cells.

Developing efficient and anti-corrosive oxygen reduction reaction (ORR) catalysts is of great importance for the applications of proton exchange membrane fuel cells (PEMFCs). Herein, we report a novel approach to prepare metal oxides supported intermetallic Pt alloy nanoparticles (NPs) via the reactive metal-support interaction (RMSI) as ORR catalysts, using Ni-doped cubic ZrO2 (Ni/ZrO2) supported L10-PtNi NPs as a proof of concept. Benefiting from the Ni migration during RMSI, the oxygen vacancy concentrations in the support are increased, leading to an electron enrichment of Pt. The optimal L10-PtNi-Ni/ZrO2-RMSI catalyst achieves remarkably low mass activity (MA) loss (17.8 %) after 400,000 accelerated durability test cycles in a half-cell and exceptional PEMFC performance (MA=0.76 A mgPt -1 at 0.9 V, peak power density=1.52/0.92 W cm-2 in H2-O2/-air, and 18.4 % MA decay after 30,000 cycles), representing the best reported Pt-based ORR catalysts without carbon supports. Density functional theory (DFT) calculations reveal that L10-PtNi-Ni/ZrO2-RMSI requires a lower energetic barrier for ORR than L10-PtNi-Ni/ZrO2 (direct loading), which is ascribed to a decreased Bader charge transfer between Pt and *OH, and the improved stability of L10-PtNi-Ni/ZrO2-RMSI compared to L10-PtNi-C can be contributed to the increased adhesion energy and Ni vacancy formation energy within the PtNi alloy.

Integrating single Ni site and PtNi alloy on two-dimensional porous carbon nanosheet for efficient catalysis in fuel cell

Integrating single Ni site and PtNi alloy on two-dimensional porous carbon nanosheet for efficient catalysis in fuel cell

Electronic Structure Engineering of Pt-Ni Alloy NPs by Coupling of Gold Single Atoms on N-Doped Carbon for Highly Efficient Oxygen Reduction Reaction and Hydrogen Evolution Reaction.

Improving the catalytic activity and durability of platinum-based alloy catalysts remains a formidable challenge in the context of renewable energy electrolysis applications. Herein, a facile and rapid photochemical deposition strategy for the synthesis of gold single atoms (Au SAs) anchored on N-doped carbon is presented. These Au SAs serve as a charge redistribution support for Pt-Ni alloy nanoparticles (PtNiNPs/AuSA-NDC), creating an extended electron-donating interface with Pt-Ni alloy sites. Consequently, the PtNiNPs/AuSA-NDC hybrid catalyst manifests exceptional catalytic performance and durability in both the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) under acidic conditions. Specifically, in ORR, it exhibits a half-wave potential (0.92V vs RHE), with a mass activity 20.4 times superior to Pt/C at 0.9V. In HER, PtNiNPs/AuSA-NDC demonstrates a notably reduced overpotential of 19.1mV vs RHE at 10mAcm-2 and a mass activity 38 times higher than Pt/C (at 0.25mV). Furthermore, this hybrid catalyst displays outstanding durability, with only an 8.0mV decay observed for ORR and a 6.9mV decay for HER after 10000 cycles. Theoretical calculations provide insight into the mechanism, demonstrating that isolated Au sites effectively modulate the electronic structure of Pt-Ni alloy sites, facilitating intermediate adsorption and enhancing reaction kinetics.

Synthesis and electrocatalytic evaluation of PtNi catalyst supported on SBA-15 modified carbon

Maximizing catalyst activity and stability while minimizing costs remains a formidable challenge. In this study, we employed the straightforward and easily executed ethylene glycol reduction method to synthesize highly active and stable Pt-Ni alloy catalysts, utilizing SBA15-modified carbon as the supporting material. Subsequent meticulous examinations delved into their physicochemical properties and electrocatalytic activities.Transmission electron microscopy (TEM) analyses unveiled a uniform distribution of PtNi particles on the support, showcasing a narrow particle size distribution centered around approximately 1.91 nm with minimal aggregation. Electrochemical assessments demonstrated that Pt3Ni/SBA15-C outperforms Pt/C, exhibiting 56 and 167 mV higher half-wave potentials (E1/2) and onset potential (Eonset), respectively. Furthermore, our meticulously prepared Pt3Ni/SBA15-C, featuring a cage structure, displayed remarkable stability while sustaining superior catalytic durability under an applied potential of +0.7 V. These findings underscore the effectiveness of the cage structure catalyst, comprising porous nanoparticles, in ensuring both catalytic activity and stability. The results collectively contribute to advancing our understanding of catalyst design and performance optimization in electrochemical applications.

Nanoporous NiPt alloy by dealloying of amorphous NiZrPt metallic glass for alkaline hydrogen evolution reaction

The development of high-performance and low-cost alkaline hydrogen precipitation catalysts is critical for the large-scale application of hydrogen energy. In this work, the nanoporous alloy catalysts were synthesized by dealloying melt-spun NiZrPt ribbons. The optimal sample after dealloying shows excellent HER performance in alkaline medium, with a small overpotential of 15 mV to deliver 10 mA cm−2 and a low Tafel slope of 20 mV/dec. The material characterization reveals that the incorporation of Ni modulates the electronic structure of Pt. After selective dealloying of Zr and Ni, a Pt-enriched nanoporous structure was formed on the catalyst surface. Meanwhile, the remaining Ni sites acted as synergistic sites to activate the Pt sites, which allowed for better hydrogen adsorption energy and faster kinetics of the catalytic reaction. Besides, the favorable mechanical flexibility of the material makes it potential for self-supporting electrode. This work presents a way to prepare low-Pt efficient catalysts by amorphous alloy dealloying.

Diastereoselective Hydrogenation of Tetrasubstituted Olefins using a Heterogeneous Pt-Ni Alloy Catalyst.

Stereoselective hydrogenation of tetrasubstituted olefins is an attractive method to access compounds with two contiguous stereocenters. However, homogeneous catalysts for enantio- and diastereoselective hydrogenation exhibit low reactivity toward tetrasubstituted olefins due to steric crowding between the ligand scaffold and the substrate. Monometallic heterogeneous catalysts, on the other hand, provide accessible surface active sites for hindered olefins but exhibit unpredictable and inconsistent stereoinduction. In this work, we develop a Pt-Ni bimetallic alloy catalyst that can diastereoselectively hydrogenate unactivated, sterically-bulky tetrasubstituted olefins, utilizing the more oxophilic Ni atoms to adsorb a hydroxyl directing group and direct facially-selective hydrogen addition to the olefin via the Pt atoms. Structure-activity studies on several Pt-Ni compositions underscore the importance of exposing a uniform PtNi alloy surface to achieve high diastereoselectivity and minimize side reactions. The optimized Pt-Ni/SiO2 catalyst exhibits good functional group tolerance and broad scope for tetrasubstituted olefins in a cyclopentene scaffold, generating cyclopentanol products with three contiguous stereocenters. The synthetic utility of the method is demonstrated in a four-step synthesis of (1R,2S)-(+)-cis-methyldihydrojasmonate with high yield and enantiopurity.